U.  S.  DEPARTMENT  OF  AGRICULTURE. 

BUREAU  OP  PLANT  INDUSTRY— BULLETIN  NO.  100,  PART  III. 

B.  T.  GALLOWAY,  Chief  of  Bureau. 


GARLICKY  WHEAT 


J.  W.  T.  DUVEL, 

Assistant  in  the  Seed  Laboratory. 


Issued  April  5,  1906. 


WASHINGTON: 

GOVERNMENT  PRINTING  OFFICE. 

1906. 


13  TL’l  C  YUXujvx-  PkjJLt,  Co  , 


CONTENTS. 


Page 


Introduction .  5 

Wheat  containing  garlic . , .  5 

Experiments  in  separating  garlic  from  wheat .  6 

Lot  A .  7 

Lot  B . . .  8  ^ 

Lot  C . 9 

The  total  cost  of  drying  and  cleaning  garlicky  wheat .  10 

The  net  cost  of  removing  garlic .  12 

The  effect  of  the  drying  on  the  milling  qualities  of  the  grain .  12 

The  effect  of  the  drying  on  the  vitality  of  the  wheat . . .  13 

Machinery  used  for  drying  and  cleaning . 14 

Summary .  14 

Description  of  plates .  16 


3 


I 


ILLUSTRATIONS. 


Plate  I.  Wheat  kernels  and  the  aerial  bulblets  of  wild  garlic.  Natural  size .  16 

II.  Figs.  1,  2,  and  3.  One-pound  samples  of  garlicky  wheat,  Lots  A,  B,  and  C, 
respectively,  as  received;  the  quantity  of  garlic  in  1-pound  samples 
when  received  and  the  amount  of  garlic  remaining  in  1-pound  samples 

after  drying  and  cleaning .  16 

4 


B.  P.  I.— 204. 


GARLICKY  WHEAT. 


INTRODUCTION. 

Wild  garlic,  Allium  vineale  L.,  was  introduced  into  the  United 
States  from  Europe  considerably  more  than  a  century  ago.  Since  its 
introduction  it  has  made  a  slow  but  steady  advance,  and  is  now 
found  growing *more  or  less  abundantly  throughout  the  greater  part 
of  West  Virginia,  Virginia,  Maryland,  Delaware,  Tennessee,  North 
Carolina,  the  northern  part  of  South  Carolina,  the  southern  part  of 
Pennsylvania,  New  Jersey,  and  Connecticut,  and  locally  in  almost 
every  State  east  of  the  Mississippi  River.  In  all  places  where  it  has 
become  well  established  it  is  a  veritable  pest  to  farmers,  millers,  grain 
dealers,  and  dairymen. 

Wild  garlic  is  one  of  the  worst  weeds  to  eradicate  after  it  has  once 
gained  a  foothold,  being  propagated  by  underground  bulbs,  aerial 
bulblets,  and  in  some  sections  by  seeds. 

WHEAT  CONTAINING  GARLIC. 

The  presence  of  wild  garlic  in  the  grain  fields  of  the  central  eastern 
States  and  in  other  sections  where  it  is  locally  abundant  has  caused  a 
very  great  loss  to  agriculture.  Farmers  have  been  obliged  to  sell  their 
garlicky  wheat  at  greatly  reduced  prices,  principally  because  foreign 
markets  will  not  buy  it  except  at  a  low  price,  and  millers  as  a  rule 
refuse  to  handle  it,  for  they  have  been  able  to  grind  garlicky  grain  only 
at  a  much'  increased  cost.  The  garlic  bulblets  gum  the  rollers,  neces¬ 
sitating  the  stopping  of  the  mills  and  the  washing  of  the  rollers  before 
the  grinding  can  be  resumed.  The  frequency  with  which  the  washing 
must  be  done  depends  on  the  quantity  of  garlic  present.  In  extreme 
cases  the  washing  must  be  repeated  every  two  or  three  hours,  the 
operation  requiring  from  ten  to  fifteen  minutes  for  each  set  of  rollers. 

Furthermore,  flour  made  from  wheat  mixed  with  garlic  bulblets  is  of 
inferior  quality,  as  bread  made  from  such  flour  has  Jhe  garlic  odor  so 
disagreeable  to  most  people.  This  is  especially  noticeable  if  the 
bread  is  eaten  warm.  Moreover,  on  boards  of  trade,  wheat  containing 
garlic  bulblets  in  considerable  quantity  is  graded  as  u  Rejected, ,J  and 
is  then  sold  only  on  sample.  Wheat  of  this  character  is  generally  sold 
at  a  price  ranging  from  20  to  40  per  cent  lower  than  No.  2  Red.  IIow- 

5 


6 


GARLICKY  WHEAT. 


ever,  if  the  garlic  bulblets  are  present  only  in  comparatively  small 
quantity  (usually  less  than  one-fourth  of  1  per  cent)  it  may  pass  as 
No.  2  Red,  depending  largely  on  the  other  foreign  substances  present 
and  the  amount  of  water  in  the  grain. 

At  present  there  are  no  available  data  showing  definitely  the  extent 
of  the  loss  due  to  the  presence  of  garlic  in  grain;  but  in  wheat  alone 
this  loss  is  known  to  be  very  great.  In  many  sections  the  growing  of 
wheat  has  been  almost  wholly  abandoned  as  a  result  of  the  reduced 
price  at  which  garlicky  wheat  must  be  sold.  An  annual  loss  of 
$1,500,000  is  undoubtedly  a  very  conservative  figure.  It  has  been 
estimated  by  members  of  the  Chamber  of  Commerce  of  Baltimore  that 
60  per  cent  of  the  wheat  grown  in  that  section  of  the  United  States 
contains  more  or  less  garlic.  The  three  States  in  which  garlic  does 
the  greatest  injury  to  the  wheat  crop  are  Maryland,  Virginia,  and 
Tennessee.  The  average  yield  of  wheat  from  these  three  States 
during  the  five  years  from  1900  to  1904,  inclusive,  was  just  short  of 
29,000,000  bushels.  Allowing  that  50  per  cent  of  this  wheat  contains 
garlic,  we  have  14,500,000  bushels  of  garlicky  wheat  in  these  three 
States  alone.  But  granting  that  only  one-half  of  this  amount  con¬ 
tains  garlic  in  sufficient  quantity  to  throw  it  out  of  grade,  we  still 
have  7,250,000  bushels  of  wheat  which  must  be  sold  at  a  greatly 
reduced  price.  A  reduction  of  only  15  cents  per  bushel  means  more 
than  a  million  dollars  annually  to  the  farmers  of  Maryland,  Virginia, 
and  Tennessee.  The  members  of  a  prominent  firm  of  grain  exporters 
in  Baltimore  state  that  the  depreciation  for  the  Maryland  crop  alone, 
which  amounts  to  about  12,000,000  bushels  annually,  will  be  fully  5 
to  10  cents  per  bushel,  or  an  equivalent  of  $600,000  to  $1,200,000.  A 
large  quantity  of  garlicky  wheat,  however,  does  not  get  into  the  ele¬ 
vators,  being  fit  only  for  feeding  purposes.  Mr.  R.  L.  Wells®  states 
that,  in  Tennessee,  wheat  containing  garlic  bulblets  has  been  sold  as 
low  as  15  cents  per  bushel  to  feed  stock. 

EXPERIMENTS  IN  SEPARATING  GARLIC  FROM  WHEAT. 

The  presence  of  the  aerial  bulblets  of  wild  garlic  in  wheat  has  always 
been  objectionable,  principally  because  of  the  extreme  difficulty  of 
separating  them  from  the  wheat.  While  some  of  the  lighter,  imma¬ 
ture  bulblets  can  be  blown  out  by  a  good  fanning  mill,  the  greater 
quantity  are  of  practically  the  same  size  and  weight  as  the  wheat  ker¬ 
nels.  Plate  I  shows  wheat  kernels  and  the  aerial  bulblets  of  wild  gar¬ 
lic  of  natural  size.  This  similarity  in  size  and  shape  makes  it  impos¬ 
sible  to  separate  them  during  the  autumn  or  early  winter  by  the  use  of 
the  ordinary  cleaning  machinery  usually  found  in  the  majority  of  flour 
mills  and  elevators,  i.  e.,  by  screening  and  fanning.  If  the  bulblets 


a  The  Wild  Onion,  Bulletin,  Tennessee  Agricultural  Experiment  Station,  July,  1895. 


EXPERIMENTS  IN  SEPARATING  GARLIC  FROM  WHEAT. 


7 


are  allowed  to  freeze,  they  afterwards  become  dry  and  are  then  quite 
readily  blown  out,  but  this  is  not  always  practicable. 

In  view  of  this  fact  experiments  were  undertaken  in  June,  1905,  in 
order  to  ascertain  whether  the  mixture  of  garlic  and  wheat  could  not 
be  dried  artificially,  thereby  reducing  the  weight  of  the  bulblets  to 
such  an  extent  that  they  could  be  satisfactorily  removed  as  soon  as 
the  grain  is  ready  for  market.  The  detailed  results  of  these  experi¬ 
ments®  are  given  in  the  following  pages. 

LOT  A. 

Lot  A  consisted  of  approximately  44  bushels  of  “ rejected”  wheat 
furnished  by  the  Baltimore  Chamber  of  Commerce.  When  received 
it  contained  16.55  per  cent  of  water  and  2.17  per  cent  of  garlic.  The 
amount  of  foreign  seed  and  chaff  present  was  not  determined.  The 
value  of  this  wheat  was  placed  at  65  or  70  cents  a  bushel. 

Experiment  No.  1. — A  portion  of  this  wheat  was  dried  in  the  small 
grain  drier  of  the  Seed  Laboratory  at  a  maximum  temperature  of  136° 
F.  for  two  hours.  During  this  time  the  moisture  content  of  the  grain 
was  reduced  from  16.55  per  cent  to  9.5  per  cent,  or  from  2|  to  4J  per 
cent  less  than  good  American  wheat  normally  contains.  But  this 
degree  of  drying  proved  insufficient,  as  0.28  per  cent  of  garlic  still 
remained  in  the  sample  after  a  preliminary  cleaning.  This  same  lot  of 
wheat  was  therefore  dried  for  an  additional  half-hour  and  the  mois¬ 
ture  content  was  reduced  to  8.94  per  cent. 

Experiment  No.  2. — Another  portion  of  seed  from  Lot  A  was  dried 
a  few  days  later  for  nearly  four  hours,  the  maximum  temperature 
reading  140°  F.  At  the  termination  of  the  drying  a  moisture  deter¬ 
mination  of  a  sample  of  this  wheat  showed  only  5.87  per  cent  of  water. 

The  wheat  from  experiments  Nos.  1  and  2  was  then  mixed  and 
cleaned,  and  the  average  percentage  of  water  in  the  mixed  sample  was 
found  to  be  7.41  per  cent.  After  cleaning,  an  analysis  of  this  wheat 
showed,  that  the  amount  of  garlic  had  been  reduced  from  2.17  to  0.05 
per  cent,  97.6  per  cent  of  the  garlic  having  been  removed.  Plate  II, 
figure  1,  shows  a  1-pound  sample  of  this  wheat  as  received,  the 
quantity  of  garlic  in  1  pound  when  received,  and  the  quantity  of 
garlic  remaining  in  1  pound  after  drying  and  cleaning. 

Concerning  this  lot  of  wheat  the  secretary  of  the  Baltimore  Cham¬ 
ber  of  Commerce  wrote  as  follows : 

The  wheat  which  you  cleaned  and  returned  was  the  source  of  a  great  deal  of  interesting 
comment  upon  the  floor  of  the  chamber,  and  the  general  idea  is  that  a  very  vast  change  was 
accomplished  by  running  it  through  the  drier.  The  sample  sent  originally  was  of  such  low 

“Acknowledgments  are  due  to  the  members  of  the  Baltimore  Chamber  of  Commerce  and 
to  Mr.  Walter  Roberts,  of  Alexandria,  Va.,  and  Mr.  E.  H.  Darby,  of  Seneca,  Md.,  who  kindly 
supplied  the  garlicky  wheat  for  these  experiments. 


8 


GARLICKY  WHEAT. 


and  inferior  grade  as  to  prohibit  it  from  going  into  the  elevators,  and  the  drying  and  cleaning 
to  which  it  was  subjected  made  it  No.  2  Red,  the  contract  grade,  a  difference  in  value  of 
fully  17  cents  per  bushel. 

An  increase  of  17  cents  per  bushel  was  equivalent  to  24.6  per  cent 
of  the  value  of  this  wheat  before  drying  and  cleaning. 

LOT  B. 

A  second  sample  of  approximately  38  bushels  of  “  rejected’ ’  wheat 
furnished  by  Mr.  Walter  Roberts,  Alexandria,  Va.,  contained  0.56  per 
cent  of  garlic  and  15.08  per  cent  of  water  and  weighed  only  57.5  pounds 
per  bushel. 

The  lot  was  divided  into  three  parts  for  treatment,  as  follows: 

Experiment  No.  3. — In  this  test  the  drying  was  continued  for  three 
hours,  the  temperature  of  the  air  varying  from  153°  to  158°  F.  and  the 
temperature  of  the  wheat  from  117°  to  155°  F.  The  moisture  was  re¬ 
duced  from  15.08  to  7.92  per  cent.  The  weight  per  bushel  was  in¬ 
creased  from  57.5  to  59.25  pounds  on  drying  and  to  60.6  pounds  after 
cleaning.  The  quantity  of  garlic  was  reduced  to  0.05  per  cent,  the 
same  as  the  combined  results  of  experiments  Nos.  1  and  2. 

Experiment  No.  4. — The  period  of  drying  in  this  experiment 
extended  over  three  and  one-half  hours,  the  temperature  of  the  air 
being  the  same  as  in  experiment  No.  3,  153°  to  158°  F.,  the  tempera¬ 
ture  of  the  wheat  gradually  increasing  from  95°  F.  at  the  end  of  the 
first  half-hour  to  145°  F.  During  the  three  and  one-half  hours’  drying 
the  water  content  of  the  wheat  was  reduced  to  6.88  per  cent  and  the 
weight  per  bushel  increased  to  59.5  pounds.  After  cleaning,  the 
weight  per  bushel  was  increased  to  60.7  pounds  and  the  quantity  of 
garlic  reduced  from  0.56  per  cent  to  0.06  per  cent.  Plate  II,  figure  2, 
shows  a  1 -pound  sample  of  this  wheat  as  received,  the  amount  of  garlic 
in  1  pound  when  received,  and  the  amount  of  garlic  remaining  in  1 
pound  after  drying  for  three  and  one-half  hours  and  cleaning. 

Experiment  No.  5. — The  last  portion  of  Lot  B  was  dried  for  two  and 
three-fourths  hours,  the  temperature  of  the  wheat  reaching  122°  F.  in 
three-quarters  of  an  hour,  and  138°  F.  after  one  hour,  which  tempera¬ 
ture  was  maintained  for  one-half  hour,  gradually  decreasing  during 
the  last  one  and  one-quarter  hours  to  117°  F.,  when  the  experiment 
was  concluded.  The  moisture  content  of  the  wheat  was  reduced  from 
15.08  to  8.48  per  cent  and  the  weight  per  bushel  raised  from  57.5  to 
58.6  pounds.  After  cleaning,  the  weight  per  bushel  was  60  pounds 
and  the  garlic  present  0.07  per  cent. 

After  drying  and  cleaning,  the  wheat  from  Lot  B  graded  No.  2  Red, 
having  at  that  time  a  value  of  85  cents  per  bushel.  As  in  its  original 
condition  the  wheat  was  purchased  for  55  cents  per  bushel,  the  drying 
and  cleaning  increased  its  value  54.5  per  cent. 


EXPERIMENTS  IN  SEPARATING  GARLIC  FROM  WHEAT. 


9 


LOT  C. 

A  consignment  of  approximately  30  bushels  of  “rejected”  wheat, 
containing  2.04  per  cent  of  garlic,  16.2  per  cent  of  water,  and  weigh¬ 
ing  only  56.5  pounds  a  bushel,  was  lent  to  the  Department  of  Agricul¬ 
ture  by  Mr.  E.  H.  Darby,  of  Seneca,  Md. 

This  lot  of  wheat  was  divided  into  two  parts  and  treated  as  experi¬ 
ments  Nos.  6  and  7. 

Experiment  No.  1 This  wheat  was  subjected  to  an  air  temperature 

of  113°  F.  for  one  hour  and  of  154°  F.  for  two  hours,  the  maximum 
temperature  of  the  grain  for  the  last  half  hour  being  149°  F.  The  mois¬ 
ture  content  was  reduced  from  16.2  per  cent  to  8.2  per  cent.  The 
weight  per  bushel  was  raised  to  57.8  pounds  after  drying  and  60.6 
pounds  after  cleaning,  and  the  amount  of  garlic  was  reduced  to  0.17 
per  cent. 

Experiment  No.  7. — This  experiment  continued  for  three  hours,  as 
in  experiment  No.  6,  but  the  temperature  of  the  air  current  decreased 
gradually  from  146°  to  122°  F.,  the  maximum  temperature  of  the 
grain  being  131°  F.  Samples  taken  at  the  termination  of  the  experi¬ 
ment  showed  a  moisture  content  of  8.83  per  cent.  The  weight  per 
bushel  was  increased  to  57.5  pounds  after  drying  and  60.2  pounds 
after  cleaning.  Plate  II,  figure  3,  shows  a  1-pound  sample  of  this 
wheat  as  received,  the  amount  of  garlic  in  1  pound  when  received,  and 
the  amount  of  garlic  remaining  in  1  pound  after  drying  for  three 
hours  and  cleaning. 

A  sample  of  this  cleaned  wheat  was  examined  by  the  chief  inspector 
of  the  Baltimore  Chamber  of  Commerce  and  graded  as  No.  2  Red,  giv¬ 
ing  it  a  value  of  84.5  cents  per  bushel.  The  highest  price  offered  for 
the  original  lot  of  wheat  was  60  cents  per  bushel.  The  removing  of 
the  garlic  and  the  cleaning  consequently  enhanced  the  value  40.8  per 
cent. 

In  experiments  Nos.  6  and  7  the  drying  was  not  continued  quite 
long  enough  for  the  best  results,  although  the  quality  of  the  wheat 
was  raised  to  “contract”  grade.  At  temperatures  from  150°  to  158° 
F.  the  drying  should  continue  for  two  and  one-half  to  three  hours,  or 
until  the  moisture  content  of  the  wheat  is  reduced  to  about  8  per  cent. 

In  none  of  the  experiments  was  it  possible  to  remove  all  of  the  garlic, 
but  in  every  case  the  quantity  was  reduced  considerably  more  than 
was  necessary  to  make  the  wheat  grade  as  No.  2  Red.  Moreover,  the 
quantity  of  garlic  present  after  the  cleaning  was  not  considered  suffi¬ 
cient  to  interfere  with  the  milling  of  the  wheat  or  to  injure  the  quality 
of  the  flour. 


10 


GAKLICKY  WHEAT. 


The  following  diagrammatic  figures  show  the  relative  quantity  of 
garlic  in  the  wheat  before  and  after  treatment: 


Percentages,  by  weight,  of  garlic  in  wheat,  Lots  A,  B,  and  C ,  before  and  after  drying  and  cleaning 


Original  sample: 
2.17  per  cent  of  garlic. 


Lot  A. 


Experiments  Nos.  1  and  2,  combined  after  drying  for  2^  and  4  hours,  respec¬ 
tively,  and  cleaning: 

0.05  per  cent  of  garlic. 

Lot  B. 

Original  sample: 

0.56  per  cent  of  garlic. 

Experiment  No.  3,  after  drying  for  3  hours  and  cleaning: 

0.05  per  cent  of  garlic. 


Experiment  No.  4,  after  drying  for  3|  hours  and  cleaning: 

0.08  per  cent  of  garlic. 

Experiment  No.  5,  after  drying  for  2|  hours  and  cleaning: 

0.07  per  cent  of  garlic. 

Lot  C. 

Original  sample: 

2.04  per  cent  of  garlic. 

Experiment  No.  6,  after  drying  for  3  hours  and  cleaning: 

0.16  per  cent  of  garlic. 

Experiment  No.  7,  after  drying  for  3  hours  and  cleaning: 

0.17  per  cent  of  garlic. 

Garlic  bulblets  as  found  in  wheat  contain  from  35  to  70  per  cent  of 
water,  while  the  water  content  of  fresh  garlicky  wheat  usually  varies 
from  15  to  20  per  cent.  During  the  drying  the  amount  of  water  in  the 
wheat  is  decreased,  but  at  the  same  time  the  kernels  become  more  com¬ 
pact  and  the  specific  gravity  is  increased,  as  is  shown  by  the  weight 
per  bushel  before  and  after  drying.  On  the  other  hand,  the  specific 
gravity  of  the  garlic  bulblets  is  lowered  by  the  drying.  The  outer 
membranous  coverings  of  the  bulblets  remain  distended  and  the 
shrinkage  takes  place  in  the  inner  portion,  thus  leaving  a  small  air 
space  between  the  bulb  proper  and  the  outer  protecting  layers.  This 
increased  air  space,  together  with  the  decreased  weight  due  to  the  loss 
of  water,  makes  it  possible  to  separate  most  of  the  bulblets  from  the 
wheat  by  ordinary  cleaning  machinery. 


THE  TOTAL  COST  OF  DRYING  AND  CLEANING  GARLICKY  WHEAT. 

The  total  cost,  including  the  shrinkage,  of  drying  and  cleaning  any 
given  lot  of  wheat  for  the  removal  of  garlic  depends  on  four  factors: 
(1)  The  amount  of  garlic  removed;  (2)  the  amount  of  chaff  and  other 


TOTAL  COST  OF  DRYING  AND  CLEANING. 


11 


foreign  substances,  aside  from  the  garlic,  removed;  (3)  the  percentage 
of  water  removed  from  the  wheat;  (4)  the  cost  of  operating  the 
machinery. 

The  amount  of  garlic  removed. — In  the  experiments  with  the  three 
lots  of  wheat  herein  described  practically  all  of  the  garlic  was  removed, 
and  this  must  be  considered  as  a  loss  in  weight.  The  average  loss 
for  each  of  the  three  lots  of  wheat  due  to  the  removal  of  garlic  was 
2.12  per  cent,  0.50  per  cent,  and  1.88  per  cent  for  Lots  A,  B,  and  C, 
respectively. 

The  amount  of  chaff  and  other  foreign  substances ,  aside  from  the  garlic , 
removed. — The  loss  in  weight  due  to  the  cleaning,  aside  from  the  quan¬ 
tity  of  garlic,  depends  entirely  upon  the  amount  of  light,  immature 
wheat,  chaff,  and  other  foreign  substances  removed.  This  loss  bears 
the  same  ratio  for  any  lot  of  wheat.  Consequently,  strictly  speaking, 
this  additional  decrease  in  weight  can  not  be  considered  as  an  extra 
expense  in  the  treatment  of  garlicky  wheat.  Moreover,  the  quantity 
of  foreign  substances  present  has  an  important  bearing  on  the  grading 
of  the  grain. 

The  following  summary  shows  the  percentages  of  screenings,  includ¬ 
ing  the  garlic,  obtained  from  the  wheat  treated  as  experiments  Nos. 
3,  4,  5,  6,  and  7 : 

Experiment  No.  3  gave  611  pounds  of  clean  wheat  and  28  pounds, 
or  4.4  per  cent,  of  screenings.  Experiment  No.  4  gave  548.5  pounds 
of  clean  wheat  and  15.5  pounds,  or  2.8  per  cent,  of  screenings.  Exper¬ 
iment  No.  5  gave  736.5  pounds  of  clean  wheat  and  26.5  pounds,  or  3.4 
per  cent,  of  screenings.  The  average  percentage  of  screenings  from 
experiments  Nos.  3,  4,  and  5  (Lot  B)  was  3.54  per  cent.  Deducting 
from  this  the  amount  of  garlic  removed  from  Lot  B,  0.50  per  cent, 
there  is  left  3.03  per  cent,  the  proportion  of  immature  wheat,  chaff,  and 
other  foreign  substances  removed. 

In  experiments  Nos.  6  and  7,  1,536  pounds  of  dried  wheat  gave  135 
pounds  of  screenings,  an  equivalent  of  8.8  per  cent,  of  which  1.88  per 
cent  was  garlic,  leaving  6.92  per  cent  of  immature  wheat,  chaff,  and 
other  foreign  substances  removed. 

The  percentage  of  water  removed  from  the  wheat. — Garlicky  wheat 
almost  invariably  contains  a  high  percentage  of  water,  and  the  greatest 
loss  in  weight  is  probably  due  to  the  liberation  of  water  during  the  dry¬ 
ing  process.  In  these  experiments  the  quantity  of  water  was  reduced 
from  16.55  per  cent,  15.08  per  cent,  and  16.20  per  cent  to  an  average 
of  7.41  per  cent,  7.76  per  cent,  and  8.52  per  cent  for  Lots  A,  B,  and  C, 
respectively.  In  order  that  the  garlic  may  be  removed  satisfactorily 
it  is  necessary  to  reduce  the  water  content  to  approximately  8  per  cent, 
which  is  from  4  to  6  per  cent  less  than  No.  2  Bed  wheat  normally  con¬ 
tains.  However,  the  dried  wheat  will  again  absorb  water  from  the 
atmosphere,  and  after  the  lapse  of  a  few  days  the  water  content  will  be 


12 


GARLICKY  WHEAT. 


practically  the  same  as  that  of  air-dried  wheat.  Likewise  the  clean, 
dried  wheat  can  be  mixed  with  any  garlic-free  lot  of  wet  wheat  and  the 
grade  of  the  latter  improved  in  this  way.  For  this  reason,  only  the 
difference  between  the  water  content  of  the  wet  garlicky  wheat  and 
that  of  No.  2  Red,  which  averages  about  13  per  cent  during  the  first 
few  months  after  harvesting,  should  be  considered  as  actual  loss  in 
weight  due  to  drying.  On  this  basis  the  loss  due  to  the  removal  of 
water  was  3.55  per  cent  for  Lot  A,  2.08  per  cent  for  Lot  B,  and  3.20 
per  cent  for  Lot  C. 

The  cost  of  operating  the  machinery. — The  cost  of  the  actual  drying 
and  cleaning  alone  is  very  small.  With  the  low  pressure  boilers  avail¬ 
able  for  use  with  the  small  grain  drier  in  the  Bureau  of  Plant  Industry 
the  maximum  temperature  possible  is  only  158°  F.  At  this  tempera¬ 
ture  it  is  necessary  to  continue  the  drying  for  from  two  and  one-half  to 
three  hours  in  order  that  the  weight  of  the  garlic  may  be  sufficiently 
reduced  so  that  it  can  be  removed.  With  the  high  pressure  boilers  such 
as  are  found  in  most  grain  elevators  and  flour  mills  an  air  temperature 
of  170°  to  180°  F.  can  be  readily  maintained,  at  which  temperature  the 
time  factor  can  be  greatly  reduced.  By  careful  calculation  it  is  be¬ 
lieved  that  the  actual  cost  of  operating  the  machinery  for  the  drying 
and  cleaning  should  not  exceed  one-half  cent  per  bushel. 

This  factor,  however,  will  vary  with  the  capacity  of  the  drier  and 
the  number  and  size  of  the  other  kinds  of  machinery  being  operated 
simultaneously  by  the  same  boilers. 

THE  NET  COST  OF  REMOVING  GARLIC. 

To  ascertain  the  net  cost  of  removing  garlic  bulblets  from  wheat  in 
order  to  bring  it  up  to  “contract”  grade,  only  the  following  items  need 
be  taken  into  consideration :  (1)  The  cost  of  operating  the  machinery; 
(2)  the  loss  in  weight  due  to  the  quantity  of  garlic  actually  removed, 
and  (3)  the  difference  in  the  amount  of  water  normally  contained  in 
good  air-dried  wheat ,  which  is  not  far  from  13  per  cent,  and  the  amount 
of  water  in  the  garlicky  wheat  before  it  goes  into  the  drier.  On  this 
basis  the  cost  of  drying  and  cleaning  the  garlicky  wheat  discussed  in 
the  foregoing  pages  was  6.3  per  cent,  3.2  per  cent,  and  5.7  per  cent,  or 
an  equivalent  of  5§  cents,  2}  cents,  and  4f  cents  per  bushel  for  lots 
A,  B,  and  C,  respectively,  as  governed  by  the  prices  current  at  that 
time. 

THE  EFFECT  OF  THE  DRYING  ON  THE  MILLING  QUALITIES  OF 

THE  GRAIN. 

No  flour  was  made  from  any  of  the  wheat  after  drying  and  cleaning; 
but  the  consensus  of  opinion  of  the  majority  of  the  millers  to  whom 
samples  of  the  dried  wheat  were  submitted  was  that  the  milling  quali¬ 
ties  of  the  wheat  had  not  been  injured  by  the  drying.  Such  wheat, 


EFFECT  OF  DRYING  ON  VITALITY. 


13 


however,  is  not  fit  for  milling  until  it  has  absorbed  water  from  the 
atmosphere,  or  has  been  mixed  with  damp  grain,  or  steamed,  in  order 
to  toughen  the  bran.  If  the  milling  is  attempted  while  the  wheat 
is  exceptionally  dry,  the  bran  will  be  easily  broken,  resulting  in  the 
production  of  coarse,  dark  flour. 

THE  EFFECT  OF  THE  DRYING  ON  THE  VITALITY  OF  THE  WHEAT. 

The  objection  has  frequently  been  made  that  the  high  temperature 
ordinarily  used  in  the  commercial  drying  of  grain  will  destroy  the 
germinating  power.  In  the  majority  of  cases  the  vitality  of  the  grain 
after  drying  is  of  little  importance,  as  such  grain  is  seldom  used  for 
sowing  or  planting.  The  foregoing  objections,  however,  are  not  well 
established,  as  the  vitality  of  grain  is  not  injured  by  drying  in  com¬ 
mercial  grain  driers  at  the  temperatures  commonly  employed. 

The  grounds  for  the  belief  that  temperatures  as  high  as  140°  to  175° 
F.  for  periods  of  short  duration  will  destroy  the  vitality  of  grains  are 
based  on  laboratory  tests  in  which  no  provision  was  made  for  the  cir¬ 
culation  of  air.  Under  such  conditions  the  life-giving  principles  are 
readily  destroyed,  especially  when  considerable  moisture  is  present. 
But  when  the  drying  is  done  in  such  a  way  that  the  moisture  liberated 
will  be  readily  carried  away,  as  in  commercial  grain  driers,  there  is 
little  danger  of  destroying  the  vitality  of  the  grains,  even  though  the 
duration  of  drying  be  several  times  greater  than  that  given  for  the 
foregoing  experiments. 

The  following  table  shows  the  effect  of  the  drying  on  the  germinat¬ 
ing  capacity  of  the  samples  of  garlicky  wheat  from  lots  B  and  C, 
already  discussed : 


Percentages  of  germination  of  wheat  from  lots  B  and  C  before  and  after  drying. 


Sample  mark. 

Dura¬ 
tion  of 
drying. 

Tempera¬ 
ture  of  a'r 
current  in 
drying. 

Maximum 
tempera¬ 
ture  of 
wheat. 

W  ater 
content 
of  wheat. 

Germi¬ 

nation. 

Hours. 

Degrees  F. 

Degrees  F. 

Per  cent. 

Per  cent. 

Original  sample . 

15.08 

80 

Experiment  No.  3 . 

3 

153-158 

155 

7. 92 

83.5 

Experiment  No.  4 . 

153-158 

145 

6.88 

85 

Experiment  No.  5 . 

2| 

155-108 

138 

8.48 

79.5 

Original  sample . 

16.20 

82 

Experiment  No.  6 . 

2h 

113-154 

149 

8.20 

83 

Experiment  No.  7 . 

3‘ 

146-122 

131 

8.83 

85 

With  but  a  single  exception  the  percentages  of  germination  were 
higher  after  the  drying  than  before,  and  such  is  generally  true.  In 
all  cases  the  germination  was  low,  due  to  the  damaged  condition  of  the 
grain  when  received. 

While  the  tests  made  are  few  in  number,  the  results  given  in  the 
foregoing  table  are  sufficient  to  show  that  a  good  quality  of  garlicky 
wheat  can  be  dried  and  afterwards  cleaned  and  used  for  sowing  with 
entirely  satisfactory  results.  The  garlic  bulblets,  as  found  in  wheat, 


14 


GARLICKY  WHEAT. 


contain  from  35  to  70  per  cent  of  water.  With  this  high  percentage 
of  water  the  greater  quantity  of  the  bulblets  are  partially  cooked  or 
scalded  during  the  drying  process,  thus  rendering  growth  impossible. 

MACHINERY  USED  FOR  DRYING  AND  CLEANING. 

The  drying  was  done  in  a  small  grain  drier.  In  the  absence  of  a 
good  fanning  and  screening  machine  for  the  larger  grains,  the  wheat 
was  first  run  through  a  fanning  mill  specially  constructed  for  cleaning 
clovers,  alfalfa,  and  timothy.  The  greater  quantity  of  the  garlic  was 
blown  out,  but  many  of  the  larger  bulblets  could  not  be  removed  in 
the  absence  of  screens,  and  for  this  reason  the  wheat,  for  the  final 
cleaning,  was  put  through  a  “shaker”  such  as  is  commonly  used  for 
cleaning  rice. 

It  is  not  desired  to  place  any  special  emphasis  on  the  particular 
machinery  used  for  these  experiments.  Any  of  the  good  commercial 
driers  with  any  good  cleaning  machinery  should  give  satisfactory 
results. 

SUMMARY. 

The  presence  of  the  aerial  bulblets  of  wild  garlic  in  a  large  quantity 
of  the  wheat  grown  in  the  central  eastern  United  States  causes  a  great 
depreciation  in  its  value.  The  loss  to  agriculture  from  this  cause 
alone  is  very  conservatively  estimated  at  more  than  $1,500,000  annu¬ 
ally. 

The  wheat  kernels  and  the  garlic  bulblets  are  very  similar  in  size 
and  weight,  which  makes  their  separation  by  the  methods  ordinarily 
in  use  next  to  impossible  as  long  as  they  are  fresh. 

If  wheat  containing  garlic  is  artificially  dried,  the  wheat  kernels 
increase  in  specific  gravity  and  the  garlic  bulblets  decrease  in  specific 
gravity,  so  that  practically  all  of  the  latter  can  be  removed  by  good 
cleaning  machinery. 

Garlicky  wheat  is  usually  wet,  often  containing  as  much  as  20  per 
cent  of  water,  and  the  drying  should  be  continued  until  the  moisture 
is  reduced  to  approximately  8  per  cent. 

In  estimating  the  total  cost  of  the  treatment  of  a  lot  of  garlicky 
wheat,  only  the  amount  of  garlic  removed,  the  excess  of  moisture 
above  that  which  good  No.  2  Red  wheat  usually  contains,  and  the 
cost  of  operating  the  machinery  need  be  considered.  The  cost  of 
removing  the  chaff,  immature  wheat,  etc.,  is  the  same  as  for  the  clean¬ 
ing  of  any  sample  of  wheat  free  from  garlic. 

The  commercial  drying  of  wheat  in  a  good  commercial  grain  drier 
does  not  injure  its  vitality,  while  most  of  the  garlic  bulblets  are  killed, 
owing  to  the  higher  percentage  of  water  in  the  latter. 

It  has  not  been  definitely  determined,  but  the  more  general  opinion 
is  that  the  drying  does  not  injure  the  milling  qualities  of  the  wheat. 

Any  of  the  good  commercial  grain  driers,  together  with  any  good 
wheat-cleaning  machinery,  should  give  satisfactory  results. 


PLATES. 


DESCRIPTION  OF  PLATES. 


Plate  I.  Wheat  kernels  and  aerial  bulblets  of  wild  garlic.  (Natural  size.) 

Plate  II.  Fig.  1. — A,  1-pound  sample  of  garlicky  wheat,  Lot  A,  as  received;  B,  amount  of 
garlic  in  1-pound  sample  when  received,  2. 17  per  cent;  C,  amount  of  garlic  remaining  in 
1-pound  sample  after  drying  and  cleaning,  0.05  per  cent.  Fig.  2. — A,  1-pound  sample 
of  garlicky  wheat,  Lot  B,  as  received;  B,  amount  of  garlic  in  1-pound  sample  when 
received,  0.56  per  cent;  C ,  amount  of  garlic  in  1-pound  sample  after  drying  and  cleaning, 
0.06  per  cent.  Fig.  3. — A,  1-pound  sample  of  garlicky  wheat,  Lot  C,  as  received;  B, 
amount  of  garlic  in  1-pound  sample  when  received,  2.04  per  cent;  C,  amount  of  garlic 
remaining  in  1-pound  sample  after  drying  and  cleaning,  0.16  per  cent. 


Bui.  100,  Pt.  Ill,  Bureau  of  Plant  Industry,  U.  S.  Dept,  of  Agriculture. 


Plate  I. 


Wheat  Kernels  (A)  and  Aerial  Bulblets  of  Wild  Garlic  (B). 
(Natural  size.) 


Bui.  100,  Pt.  Ill,  Bureau  of  Plant  Industry.  U.  S.  Dept,  of  Agriculture. 


Plate  II. 


Fig.  1. — Wheat  and  Garlic  from  Lot  A. 


Fig.  2. — Wheat  and  Garlic  from  Lot  B. 


Fig.  3. — Wheat  and  Garlic  from  Lot  C. 

One-pound  Samples  of  Garlicky  Wheat  as  Received  (A,  A,  A);  the  Quantity  of 
Garlic  in  One-pound  Samples  when  Received  IB,  B,  B);  the  Amount  of  Garlic 
Remaining  in  One-pound  Samples  after  Drying  and  Cleaning  (C,  C,  C). 


3  0112  0732 


5357 


